Ancient Microbes, Dark Matter Stars, and Comets: Science Stories with Joe Johnson

From 40,000-year-old microbes thawed from Arctic permafrost to distant “dark matter” stars billions of light-years away, Radio Catskill’s resident science expert Joe Johnson shares a snapshot of the latest discoveries reshaping our understanding of Earth and the universe.

Microbes Thaw After 40,000 Years
A recent study in the Journal of Geophysical Research shows that microbes—bacteria and fungi—from the late Pleistocene can survive tens of thousands of years in Arctic permafrost and spring back to life.

“These microbes started reproducing very slowly at first,” Johnson explained. “But after six months, they really took off—they’re now thriving like modern organisms.”

The research has major implications for climate change. As these ancient microbes metabolize organic matter, they release carbon dioxide and methane, potent greenhouse gases. “If this permafrost melts, it could create a feedback loop,” Johnson said. “Greenhouse gases warm the atmosphere, which melts more permafrost, which releases more gases. The permafrost actually contains more organic carbon than what’s already in the atmosphere.”

Dark Matter Stars Illuminate the Early Universe
On a cosmic scale, scientists are studying “supermassive dark stars”—hypothetical first-generation stars powered by dark matter. Using the James Webb Space Telescope, researchers discovered four ultra-luminous objects whose light started traveling toward Earth more than 13 billion years ago.

“These stars are about a million times the mass of the sun and a billion times as luminous,” Johnson said. “They’re bright, diffuse, and puffy—the first stars in the universe. Discovering them helps explain very old galaxies and may show how supermassive black holes formed.”

While promising, Johnson cautioned, “We still don’t know exactly what dark matter is. This doesn’t solve the ultimate mystery, but it’s a step forward.”

Comets Lighting Up the Sky
Closer to home, two comets are visible this fall. Comet C/2025 A6 Lemmon, discovered in January, appears in the northwest sky and will be brightest between October 21 and November 8. Comet C/2025 R2 Swan, spotted in SOHO spacecraft data, is visible in the south-southwest sky but is dimmer and requires binoculars.

“Pick a dark spot with a clear horizon, let your eyes adjust, and use stars or a sky app to find them,” Johnson advised. “The best viewing is shortly after sunset. Wait too long and they’ll already be gone.”

Image: Robyn Barbato of the Cold Regions Research and Engineering Laboratory drills a sample from the walls of the Permafrost Tunnel. (Credit: Tristan Caro)